This section provides background information related to the present disclosure which is not necessarily prior art.
Many modern electronic systems demand high current slew rates. Such fast transient step loads require careful design of the voltage control loop and output filter of a power converter to keep voltage overshoots and undershoots within required specifications. This often results in a reduction in the output inductor and an increase in the switching frequency.
In a typical PFC boost pre-regulator, large voltage swings in the bulk power supply are an important factor for determining bulk capacitor specifications. For example, a typical PFC boost rail for regulating a voltage of 390 volts often requires a 450 volt bulk capacitor because the voltage over shoot during a load dump could be as high as 430 volts.
Similarly, in a typical voltage regulator module (VRM), a large number of expensive load capacitors are often used to meet high current slew rates. Because of this, a VRM typically includes smaller value output inductors and higher switching frequencies. Additionally, VRMs often utilize very high gains to respond to very small changes in output voltage. This can create stability problems in some VRMs.